You are looking at the HTML representation of the XML format.
HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <querypage name="Ancientpages">
      <results>
        <page value="20120319232034" timestamp="2012-03-19T23:20:34Z" ns="0" title="Getting Started with MediaWiki" />
        <page value="20121029165105" timestamp="2012-10-29T16:51:05Z" ns="0" title="Media" />
        <page value="20130605232303" timestamp="2013-06-05T23:23:03Z" ns="0" title="Rich Objects API" />
        <page value="20130605232640" timestamp="2013-06-05T23:26:40Z" ns="0" title="Collections API" />
        <page value="20130605232733" timestamp="2013-06-05T23:27:33Z" ns="0" title="Maps API" />
        <page value="20130605233200" timestamp="2013-06-05T23:32:00Z" ns="0" title="The HyperCities API" />
        <page value="20130605234246" timestamp="2013-06-05T23:42:46Z" ns="0" title="Debugging the Google Earth Plugin" />
        <page value="20130606034802" timestamp="2013-06-06T03:48:02Z" ns="0" title="Upgrading to PHP 5.3" />
        <page value="20130606035019" timestamp="2013-06-06T03:50:19Z" ns="0" title="Installing a HyperCities Instance" />
        <page value="20130606035649" timestamp="2013-06-06T03:56:49Z" ns="0" title="Database Structure" />
      </results>
    </querypage>
  </query>
  <query-continue>
    <querypage qpoffset="10" />
  </query-continue>
</api>